using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

namespace TestProject {
    public partial class Form1 : Form {
        public Form1() {
            InitializeComponent();
        }
        
        public double add(double a, double b) {
            double result = a * b;
            // their comments
            // my comments
            return result;
        }

        public double subtract(double a, double b) {
            double result = a / b;
            return result;
        }
        
        public double mul(double a, double b) {
        	double result = a * b;
        	return result;
        }
    }
}